1. Field of the Invention
The present invention involves the field of electronic air purification and, more specifically, a miniature device that generates a corona discharge to detoxify, and circulate air around an individual's face.
2. Description of Related Art
The present invention represents an improvement to the instant inventor's earlier invention entitled "Miniature Air Purifier" filed Feb. 6, 1995, and now issued as U.S. Pat. No. 5,484,472. That patent describes a miniature wearable unit that directs a current of ionized air towards the face of a wearer to help prevent the inhalation of various toxins and irritants that are increasingly present in our environment. For a summary of various earlier approaches to the problems of ameliorating contaminated air, the reader is directed to that earlier patent which is incorporated herein by reference.
The problem of air pollution can hardly be overstated. It has been variously estimated that as many as 80 million Americans suffer from air pollution that results in large numbers of premature deaths each year. It has been reported that children growing up in especially polluted areas like the Los Angeles basin end up with permanently damaged lungs. The problem may be even more acute in large cities of the Third World where environmental controls are more lax than in the United States. While increased governmental regulation poses one solution to the danger, what are affected individuals to do in the meantime? One can install various home air purifying devices, but this does no good when one has to travel about away from the home.
The present inventor has previously offered a portable air purifier as a solution. This earlier miniature air purifier was characterized by its small size allowing it to be worn clipped to one's clothing or on a cord about one's neck. However, the need to incorporate fairly complex electronic circuit board including two inductor components resulted in the unit having a dimension of at least 21/2.times.4.times.1 inches and weighing at least 7 oz. The circuit of that device required a significant current flow from the battery, which considerably limited battery life. Typically, the unit would operate for about 10-15 hours using a fresh alkaline battery.
The primary routes of air purification in the earlier air purifier were chemical destruction of pollutants by ozone and the corona discharge and electrostatic precipitation of particulates as a result of charging by negative ions. The primary source of air flow was a mass air flow due to acceleration of negatively ionized air molecules towards a grounded metallic grid.
Because ozone can be irritating to the respiratory system, it is desirable to provide a more effective corona discharge for destroying a wider range of chemical pollutants while, at the same time, limiting the amount of ozone emitted. There remains a considerable need for a miniature air purifier that is very efficient at producing a corona discharge for better removal of pollutants and longer battery life with minimal emission of ozone.